[PATCH] blkcg:fixes memory leaks in blkg_conf_prep()

[Wu Bo]

blkg_conf_prep():
 
new_blkg = blkg_alloc(pos, q, GFP_KERNEL);
...
blkg = blkg_lookup_check(pos, pol, q);
if (IS_ERR(blkg)) {
        ret = PTR_ERR(blkg);
        goto fail_unlock;
}
...


if calling blkg_lookup_check() failed, at the IS_ERR block, 
the new_blkg should be free before goto lable fail_unlock
in blkg_conf_prep() function.

Signed-off-by: Wu Bo <wub...@huawei.com>
---
 block/blk-cgroup.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 930212c..afeb769 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -682,6 +682,7 @@ int blkg_conf_prep(struct blkcg *blkcg, const struct 
blkcg_policy *pol,
                blkg = blkg_lookup_check(pos, pol, q);
                if (IS_ERR(blkg)) {
                        ret = PTR_ERR(blkg);
+                       blkg_free(new_blkg);
                        goto fail_unlock;
                }
 
-- 
1.8.3.1